App Store chief says Apple aimed to level playing field for developers

Apple tightly controls the App Store, which forms the centerpiece of its $46.3 billion(35.96 billion pounds)-per-year services business.Developers have criticized Apple's commissions of between 15% and 30% on many App Store purchases, its prohibitions on courting customers for outside signs-ups, and what some developers see as an opaque and unpredictable app-vetting process.